My bum hurts me. What can I do? - Anonymous
At the risk of some immature goofball laughing his/her head off at my gullibility, I'm going to assume that this is a real question & answer it.
I can empathize with your situation but there's only one thing I can say: See a doctor. Don't be embarassed, just do it. As healthcare workers, they've seen things that you can't even imagine.
Don't ever feel ashamed or uncomfortable discussing your problems or concerns with a professional. They're trained to help you without judging or blaming & their job is to make you better, as well as educating you to prevent further problems.
If you don't have insurance, you need to go online to locate a free clinic or reduced-fee program in your area. There are a number of such places in our local area.
There are countless things that could be causing your discomfort & you didn't give me a whole lot of information to narrow it down.
For the record, even a very detailed description would likely have received the same response so there's no need to elaborate.
It could be an external problem such as a splinter, insect sting or puncture in the fleshy area which can be very painful (I speak from personal experience here).
It could be an internal problem such as hemorrhoids (swollen veins) or a blockage of some sort.
Another potential culprit of mayhem is your diet. An unhealthy diet can cause all sorts of problems so it may be something as simple as a lack of fiber or insufficient hydration.
Whatever the cause, you won't be able to rectify it (no pun intended, I swear) without professional assistance. Don't delay, see a doctor or nurse & feel better soon.